I Think, Therefore I Communicate

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I Think, Therefore I Communicate

Moving chess pieces by thought alone might have been in the realm of science fiction once. Not anymore.

For Jessica Bayliss, a researcher who has been working on brain-computer interfaces, or BCIs, at the University of Rochester, it's simply the next challenge on her list.

For the past 15 years, researchers have been trying to develop BCIs to tap into the brain waves of individuals who are unable to communicate with the outside world. The goal of all BCI research is to create a direct link between computers and the electrical signals in the brain of these so-called "locked in" individuals so they can operate devices like wheelchairs or use simple word processing programs to express their wishes.

While no actual BCI products are currently on the market, researchers are making progress. Interfaces are being developed that can control basic environmental factors (such as the temperature of a house or a light switch), answer yes-or-no questions, and operate a word processor at slow rates (about one to two words a minute).

Present-day BCIs attempt to discern the intent of the user through two approaches – by reading electroencephalogram signals off the scalp with the help of a skullcap or by interpreting neural activity as recorded by electrodes implanted directly on the brain. These signals are then translated into commands that can direct a computer display or some other device.

In the virtual apartment designed by Bayliss, volunteers equipped with a virtual-reality headset have been able to switch lights on and off, bring a mock car to a stop and turn on a television set just by thinking. Though it sounds like thought reading, Bayliss insists BCIs aren't able to read minds just yet

"You can't pick up on individual thoughts," said Bayliss. "If I'm standing next to you in a soccer game, I'll hear if you call my name. If I'm three city blocks away from the game, I won't be able to hear if you call my name. This is very similar to what happens when you put electrodes on the scalp – it's like being three blocks away from what's happening in the brain."

While the EEG monitors brain activity, so a person's intent could in theory be understood, the issues that have to be resolved before anything resembling thought recognition can happen are monumental. The skull muffles much of the brain activity, and since everything a person is thinking, doing, seeing and hearing – from eye blinks to muscle movements – is encoded into the EEG signals, the number of variables researchers have to cope with is considerable.

"The challenge is to distinguish the patterns related to the inspected phenomenon," said Laura Laitinen, a researcher at the Helsinki University of Technology in Finland who is working on creating a virtual keyboard.

That said, scientists hope to isolate task-related brain patterns with a good degree of accuracy. A computer then could translate the patterns into commands.

Chuck Anderson, a professor at Colorado State University, is studying five separate mental tasks, including writing a letter, performing complex multiplication problems and visualizing numbers being written on a board.

While he is able to detect which of these tasks a subject performs with up to 70 percent accuracy by analyzing brain waves, that's just the start of what researchers need to understand in order to engineer tasks like these, let alone more complex ones like driving a car.

"The biggest problem is to distinguish a BCI command to steer a little left versus any other spontaneous EEG generated by the person," Anderson said. "How will the BCI system discriminate between the person's intention to turn left and the person's thoughtful consideration of right versus left as they are making up their decision?"

Based on the research of neuroscientists at Brown University whose work enabled monkeys to play computer games and control robotic devices using thought alone, the trials will allow up to five severely disabled patients to receive permanent implants designed to enable them to communicate with a computer.

The technology looks promising, but extensive research still needs to be done before it can be considered safe.

"Invasive BCI haven't been much tested with humans yet," Laitinen said. "At present it is even questionable if electrodes should be installed in peoples' brains."

Though BCIs cannot use EEG signals to communicate at even half the speed of a person talking at a normal rate, there are many potential applications for the technology.

It could allow disabled people to control prosthetic devices. BCIs also could lead to the development of an entirely new class of video games, or "mental typewriters" which translate thoughts into cursor movements. The military is interested in using BCIs to make faster responses possible for fighter pilots.

And mind reading? "I don't believe the technology will advance to the point of completely reading thoughts," Anderson said. "We will probably be able to identify the kind of mental activity. We should be able to distinguish between thoughts involving a memory of a piece of music versus memory of an image, for example."